#define _CRT_SECURE_NO_WARNINGS 1
#pragma once
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>


struct Node {
	int val;
	struct Node* next;
	struct Node* random;
	
};


struct Node* newnode(int x);
struct Node* exnewnode();
struct Node* copyRandomList(struct Node* head);